A common argument for expanding renewable energy sources is that technologies such as solar panels and wind turbines are responsible for far less carbon dioxide than power plants that burn fossil fuels. But two other powerful benefits should also be getting much more attention: the switch can save vast quantities of freshwater, and can create a large number of new, high-paying jobs. Want proof? Let’s look at the data that our detailed research has revealed.

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Only about 3 percent of the Earth’s water is freshwater.

Credit: Anna Hazard; Source: Water in Crisis: A Guide to the World’s Fresh Water Resources, edited by Peter H. Gleick. New York, New York: Oxford University Press, 1993

Most of that is frozen in glaciers—which means only 0.8 percent of the planet’s water reserves can be tapped for human use. Water is a precious, but limited, commodity. And nearly 1 billion people worldwide lack access to clean water.

In the U.S., 45.3 percent of the water withdrawn from lakes, rivers and underground aquifers is used to cool off thermoelectric power plants: nuclear reactors and plants that burn fossil fuels.

Credit: Anna Hazard; Source: Estimated Use of Water in the United States in 2010, by Molly A. Maupin et al. U.S. Geological Survey, 2014

This is more water than used nationwide for irrigation, and it far exceeds any other source of demand, including public consumption.

To provide electricity for an average home, a nuclear power plant requires 615 gallons of cooling water a day, a coal-fired plant requires 199 gallons per day, and a natural gas power plant requires 114 gallons per day. The stunning volume is a quiet thief that threatens the U.S. water supply.

But to make sure we are comparing apples to apples, let’s look at how much water each power source withdraws to generate one megawatt-hour of electricity.

Nuclear reactors are the highest, at 13,000 gallons. Then comes concentrated solar (heating a fluid with the sun), coal, natural gas and biomass such as wood. The water needed by solar panels and wind turbines is orders of magnitude lower. Note that these data only reflect operations to generate electricity; they do not include water used to obtain the fuel or generate the power, which can be substantial. For example, fracking can use hundreds of thousands of gallons each time a rock deposit is cracked to release natural gas.

A portion of the water extracted is lost to evaporation. The rest is sent back to the environment, but some of that is contaminated with chemicals, and most of it is hot, which can kill fish and plankton and stress the ecosystem.

Making matters worse, the power sources that have high water withdrawal per MWh are also the largest suppliers of electricity.

Natural gas, coal and nuclear power plants ranked one, two and three in 2016, in terms of the total amount of U.S. electricity generated in a year. And natural gas is projected to become even more important through 2050.

From the point of view of conserving freshwater, it seems clear that the country should shift toward renewables. This move would make more freshwater available for food production and human consumption, particularly as population grows. It would also significantly reduce greenhouse gas emissions.

Credit: Anna Hazard; Source: U.S. Energy and Employment Report, U.S. Department of Energy. January 2017

It turns out that expanding renewables creates far more jobs than expanding fossil-fuel and nuclear power plants combined. Some of the benefit is from construction jobs to build out solar infrastructure. U.S. coal and oil jobs have been disappearing, and the delivery and burning of more natural gas adds few jobs because the operations are highly automated, requiring few people. (“Other” represents jobs that cannot be assigned to a single category because they cut across multiple energy sectors.)

The answer is called the levelized cost of energy: the total expense required—capital investment, operations, fuel and so on for a power plant’s lifetime—divided by the total energy that plant could produce in that time.

Fuel and operating expenses are very high for fossil and nuclear plants, and are very low for solar and wind. The bottom line is that the levelized cost of electricity from solar panels and wind (on land) is very similar to that of natural gas. And electricity cost from those technologies is less than that from nuclear and especially clean coal. (Oil is not included because it is disappearing as a fuel for electricity generation in the U.S.)

These data and calculations make it apparent that a big shift to renewable energy in the U.S. can greatly reduce water use, lower carbon dioxide emissions, create new high-paying jobs and keep electricity costs low.

The same transition could benefit other countries as well. Electricity already costs much more in Germany and Ireland. Unemployment is high in many countries. Today many people worldwide do not have access to safe, clean water. And hundreds of thousands of people die each year because of poor sanitation, which in many places could be greatly improved using water for sewage systems.

Switching to renewable energy can help the world conserve water for personal use, sanitation and food production, and help improve living standards with good jobs. The move could help solve these interdependent issues together.

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